TREE-KANGAR O OS. 
247 
elbow, appears to be very similar in its habits. In the north of the continent, and 
on some of the small adjacent islands, the genus is represented by the spectacled 
hare-wallaby (L. conspicillatus), distinguished by its broader and heavier muzzle, 
shorter ears, the rufous tinge round the eyes; and the presence of two light bands 
on the flanks. 
Muller’s kangaroo (JJorcopsis muelleri) is one of a group of 
Dorca Kangaroos. . . ' 0 1 
three Papuan species connecting the true kangaroos with the under¬ 
mentioned tree-kangaroos. They are medium-sized animals, the length of the 
head and body in Muller’s kangaroo being about four inches greater than in the 
brush-tailed rock-wallaby; while in D. luctuosa it is about as much less. These 
kangaroos differ from the forms hitherto noticed in that the hair on the nape of 
the neck is either completely or partially directed forwards ; while the dispro¬ 
portion between the fore and hind-limbs is very much less marked. The large 
and broad muzzle is devoid of hairs, the ears are small, the tail has an almost 
naked tip, and the claws of the hind-feet are not concealed by hair. The teeth 
are distinguished by the great length, from front to back, of the permanent 
premolar in each jaw, which has a development similar to that which obtains in 
the potoroos. There is a well-developed upper tusk; and the molar teeth have 
low, rounded crowns, in which there is scarcely any trace of a longitudinal bridge 
connecting the two transverse ridges. Moreover, instead of converging at their 
extremities, the two series of cheek-teeth run nearly, or quite parallel. Muller’s 
kangaroo has short, close, and glossy fur, of a general uniform chocolate-brown ; 
but with a white stripe on the front of the hips, and the fore-arms and feet 
whitish. Externally this animal presents a remarkable resemblance to the Aru 
Island Wallaby {Macropus brunii). 
In the dense tropical forests of New Guinea and the north of 
Tree Kangaroos. Q ueens j an( j are f 0 und tree-kangaroos; and it is evident that these are 
specially modified types which have taken to this mode of life, and are in no 
way connected with the ancestral forms of the family. The tree-kangaroos are 
easily recognised by the general proportions of the two pairs of limbs to the body 
being normal: the length of the front pair being only slightly less than that of the 
hinder. The broad muzzle is only partially naked; and the hair of the nape, and 
in one species that of the back also, is directed forwards. In the hind feet the 
claws of the united second and third toes are nearly as large as those of the others : 
the latter being curved. The tail is very long, and thickly furred. I 11 the teeth, 
the permanent premolar is less elongated from front to back than in the last 
genus. Of the four well-defined representatives of the genus, the figured black 
tree-kangaroo of New Guinea {Dendrolagus ursinus) is characterised by its general 
black colour and whitish face; the length of the head and body of the female being 
20J inches, and that of the tail 23 inches. On the other hand, the brown tree- 
kangaroo {D. inustus ) of New Guinea, and the Queensland tree-kangaroo (D. 
lumholtzi), have the back greyish, and the face (and in the Queensland species the 
paws) black. Finally, Doria’s tree-kangaroo (D. dorianus), of south-eastern New 
Guinea, differs from all the others in having the fur of the back directed forwards. 
Comparatively little is known of any of the species in their native haunts: 
although it appears that they spend most of their time in the trees. Dr. 
